Maria S Altieri, Gabriel Pagnotti, PhD, Angelique Corthals, MD, Kenneth Shroyer, MD, PhD, Aurora Pryor, MD, Rashid Kikhia, MD, Mark Talamini, MD, Dana A Telem, MD. Stony Brook University Hospital
Introduction: Autologus augmentation of wound remodeling with platelet concentrate is a burgeoning field with promising results. Filtered plasma concentrate (fPC) is comprised of growth factors essential during the proliferative phase of wound healing. fPC stimulates fibroblast proliferation making it an ideal catalyst to increase collagen synthesis and deposition. We hypothesized that the addition of fPC to an acellular biologic graft would improve crural healing and tissue remodeling in hiatal hernia repair.
Methods: Sixteen healthy Yorkshire male pigs were divided into three groups: Hiatus repair (HR) (n=5), HR with biologic graft (n=5), and HR with biologic graft and fPC (n=6). All surgeries were performed in a standardized fashion by a single surgeon. For the fPC group, 60mL of blood was drawn prior to procedure and processed sterilely through a point-of-care blood filtration system. The graft was saturated with 6 mL fPC for 30 minutes based on prior kinetic studies to maximize adherence. 1 mL was reserved for platelet count and functional analysis. Animals were euthanized at 8-weeks and the distal esophagus with hiatus was harvested en-block. A blinded histopathologist graded tissue for collagen deposition and vascularization at the graft-hiatal interface. Tensile strength testing was performed with the Teststar IIs (MTS), coupled with a strain extensometer (Epsilon). Samples were pre-loaded to 1N and deformed at a constant rate of 0.2mm/s. Analysis was performed via one-way analysis of variance.
Results: On gross examination, no animal had hiatal hypertrophy or esophageal kinking or obstruction. Animals in the fPC group had significantly increased mean collagen deposition (3.3+/-1.2 vs 1.8+/- 1.3, 1.5 +/- 1.1, p=0.04) compared to HR alone and HR + biologic graft. Vascular deposition did not differ between groups (p= 0.9). A trend towards increased ultimate strength, defined as the force resulting in tissue failure, was 10.4 +/- 9.0 in the fPC group compared to 3.7 +/- 3.5 and 5.3 +/- 4.4 in HR and HR+biologic graft groups, respectively (p=0.17). Aspirate analysis revealed a mean platelet count of 3million platelets/1mL of aspirate.
Conclusion: Autologous augmentation of a biologic graft with fPC significantly increased collagen deposition at the hiatus. No evidence of excessive hiatal hypertrophy was grossly or microscopically appreciated. A trend towards increased ultimate strength of the fPC group was also demonstrated. Use of autologous fPC appears a safe and promising adjunct to wound remodeling and healing in a swine model. Planning is underway for human trials.